Rock-drill.



H. J. HIBSCHLE.

ROCK DRILL.

APPLIOATION FILED AUG. 10, 1908.

Pat e 'nted June 8, 1909.

' INVENTOR flrmoqJZZ-SCHQ.

WITNESSES ingsin which like letters an time" STATES PATENT OFFICE.

. HERMAN J. HIBSGHLE, OF VICTOR, COLORADO, ASSIGNOR TO THE MACGORMIOK DRILL AND MANUFACTURING COMPANY, INCORPORATED, 01'? DENVER, COLORADO.-

noc'xmnrm v To all whom it may concern: V Be it'known that I, HERMAN J. HrBsoHLE, residing at Victor, in the county of Teller and State: of Qolorado, have invented certain new and useful Improvements in Rock Drills, of which. the following is a specification.

I My invention relates to certain new and useful improvements in rock drills, pneumatic hammers and the like, and in its generic nature the inventionseeks to provide a drill of an improved type wherein the wearing surface between the hammer piston and'the casing may be renewed by the provision of a bushing, insertible in the casing, and around 'the hammer piston to take the place of the worn parts of the casing.

, More s-ubo'rdinately my invention embodies those novel details of construction, combination and arrangement of parts, all of which will be first described in detail, and

then be specifically pointed out in the appended claims reference beinghad to the accompanying drawings in which:

. Figure 1 is a side elevation of a part of the rock drill embodying my invention. Fig. 2, is an enlarged central vertical longitudinal section and part elevation, parts being broken away. Fig. 3, is a side elevation of the removable bushing or sleeve. Fig. 4, is an end elevation thereof looking at the smaller 'end. Fig. 5, is an end elevation of the bushing shown in Fig. 3, looking at the larger end.

Referring now to the accom anying drawnumerals of reference indicate like'parts in all of the figures, 1 represents the main body portion of the casing which has the front reduced portion I, and which is closed at the opposite end by a back head plug 2 which carries the control valve 5, as indicated in Fig. 1.

The casing 1, is provided with the internal chamber 1 wherein the hammer piston -3 operates. The chamber 11 has a )ortion of large bore 1 and a portion of smalier bore 1* merging therewith, and at the juncture of the bores 1 and 1 the casing is provided with an internal annular groove 1 which connects with the working agent port 1 d that in turn communicates with the passage 2 in (he back head ilug .3 through a radial port or parts an the annularport 2 of the Patented June 8, 1909.

back head plug, as indicated in Fig. 2 of the drawings.

The portion of the internal bore of the body portion of the casing of lesser diameter 1* is provided with an internal annular groove 1 that communicates with the exhaust passage 1 that passes the exhausted working agent to atmosphere, as indicated in Fig. 2. p v

The front part 1 0f the casing is provided with an internal bore 1, in whichv the ham:

mer head 3 d of the hammer piston 3 operates to impact the striking plug 1 The hammer piston 3 may be with packing rings 3 and is provi ed with the piston head 3 which Works in the casing chamber 1*, while the bottom portion proper of the piston 3 works 'in the reduced bore P of the casing. I

The piston 3 is rovided with the ports 3 as indicated, for t e )assage of the working agent, in a manner w ich will be readily un-' derstood by'reference to the drawings.

In order to provide a bearing for the ham mer piston'3'within the casing which may be renewed when worn, or in order to rovide bearing to be inserted into drills w ich have become worn bythe reason of the action of the hammer 'iston 3 on the casing walls,'I provide a bushing 4 of a softer material than the piston 3, or the casing 1, preferably, the bushing 4'is made of hard brass when the casing 1 and piston 3 are iron or steel, and in order that-the bushing; may .be held in )lace within the casingimmovableyit is ma e to fit the two bores 1 and 1 I of the casing. To this end the bushing 4 is provided with a portion of large diameter 4: and a portion of smaller diameter 4 as indicated, the bushing 4 being held in place-by the back head plug 2 when screwed home.

Each section 4 and 4 of the bushing 4 is provided with a series of circumferentiall y grovid ed arranged grating ports L 1 which register with the annularports 1 and 1 respectively of the casingl, t e ports 4 and 4 being in the nature of gratings, that is, of small area so that the packing rings 3 of the piston. 3 will not be scratched as the piston reciprocates within the casing. r I

'In practice the drill may be constructed withv the bushing 4 omitted, andwhen the drill casing and piston wear down so that the 'a removable bushing inposition between the hammer piston-and the interior wall of the casing said bushing consisting of a tubular member having walls of the same thickness throughout.

2. A rock drill comprising a hammer casinghaving a main body portion and a front end portion, said body portion having a bore of two diameters, and said front end having a bore merging with that of the body portion, a hammer piston operatable within the main body portion bore and having a head shaped to project into the bore of the front end portion of the casing at times, said hammer piston having a solid core portion throughout its length and in" al-inement with said head, said piston having a series of longitudinal bores surrounding said core and having radial'bures registering withsaid longitudinal bores, said casing having a substantially annular air inlet groove in the portion of greatest ;bore, means for leading compressed air or working agent into said groove to o erate said piston, said casing having a suostantially annular exhaust groove in its portion of lesser bore, and having an exhaust passage for leading the exhaust to the atmosphere from said exhaust groove, and a removable bushing interposed between the hammer piston and the casing.

3. A rock drill comprising a hammer oasing having a bore, of a plurality of diameters, and a hammer piston operatable within said bore combined with a removable bushing interposed between the hammer piston and the casing said bushing having a plurality of diameters to correspond to those of the hammer casing, the walls of said bushing being of the same thickness throughout.

4. A rock drill comprising a hammer casing having a bore, of a plurality of diameters, a hammer piston operatable within said bore combined with a removable bushing interposed between the hammer piston and the casing, said casing bore having a plurality of annular grooves, one in communication with the working agent source of supply and the other in communication with the atmosphere and said bushing having a plurality of gratingportions to aline with said grooves.

5. A removable bushing for rock drills and the like comprising a tubular body whose walls are of the same thickness throughout, said tubular body having a plurality of diameters and provided with a plurality of sets of apertures forming grating portions.

6. A bushing for rock drills and. the like comprising a tubular body having a series of longitudinally arranged rectangular apertures lying parallel with the axis of the bushing and forming a grating portion.

7. A rock drill comprising a hammer casing having a bore of a plurality of diameters,

a hammer piston having a plurality of diameters and operable within said here, combined with a soft metal removable bushing interposed between the hammer piston and the casing, said bushing having two diameters and formed with its walls of the same thickness throughout, said casing bore having a plurality of annular grooves,one in communication with the working agent source of supply and the other in communi cation with the atmosphere, the said bushing havinggrating apertures in alinement with said grooves.

HERMAN J. l-llBSGHlilC.

Witnesses:

A. 'l. MoCAnirnY, CHRISTIAN W. SOHAEFER. 

